Build Scalable, Secure
Django Web Apps
That Drive Real Growth

from django.db import models
from django.utils.translation import gettext_lazy as _

class Product(models.Model):
    """Core product model with audit fields."""
    name       = models.CharField(max_length=255)
    sku        = models.CharField(max_length=64, unique=True)
    price      = models.DecimalField(max_digits=10,
                                       decimal_places=2)
    category   = models.ForeignKey(
        'Category', on_delete=models.PROTECT,
        related_name='products'
    )
    is_active  = models.BooleanField(default=True)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering      = ['-created_at']
        indexes       = [models.Index(fields=['sku']),
                         models.Index(fields=['is_active'])]
        verbose_name_plural = _('products')

from rest_framework import serializers
from .models import Product, Category

class CategorySerializer(serializers.ModelSerializer):
    class Meta:
        model  = Category
        fields = ['id', 'name', 'slug']

class ProductSerializer(serializers.ModelSerializer):
    category = CategorySerializer(read_only=True)
    category_id = serializers.PrimaryKeyRelatedField(
        queryset=Category.objects.all(),
        source='category', write_only=True
    )
    class Meta:
        model  = Product
        fields = ['id', 'name', 'sku', 'price',
                  'category', 'category_id', 'is_active',
                  'created_at']
        read_only_fields = ['id', 'created_at']

from celery import shared_task
from django.core.mail import send_mail
from .models import Order

@shared_task(bind=True, max_retries=3,
             autoretry_for=(Exception,))
def fulfill_order(self, order_id: int) -> None:
    """Async order fulfillment — runs in Celery worker."""
    order = Order.objects\
        .select_related('user', 'address')\
        .get(pk=order_id)

    order.update_stock()
    order.mark_confirmed()

    send_mail(
        subject=f'Order #{order.pk} confirmed!',
        message=order.confirmation_body(),
        recipient_list=[order.user.email],
        from_email='orders@advertsneak.com',
    )